CacheManager Class
The CacheManager wraps a Cache enforcing that only the public API surface area is exposed.
Hence, it is the value of Store.cache
, wrapping
the cache instance returned by Store.createCache
.
It handles translating between cache versions when necessary, for instance when a Store is configured to use both a v1 and a v2 cache depending on some heuristic.
Starting with the v2 spec, the cache is designed such that it must be implemented as a singleton.
Item Index
Methods
- changedAttrs
- changedRelationships
- clientDidCreate
- commitWasRejected
- didCommit
- diff
- dump
- fork
- getAttr
- getErrors
- getRelationship
- hasChangedAttrs
- hasChangedRelationships
- hydrate
- isDeleted
- isDeletionCommitted
- isEmpty
- isNew
- merge
- mutate
- patch
- peek
- peekRequest
- put
- rollbackAttrs
- rollbackRelationships
- setAttr
- setIsDeleted
- unloadRecord
- upsert
- willCommit
Methods
changedAttrs
-
identifier
Query the cache for the changed attributes of a resource.
Parameters:
-
identifier
Object
Returns:
changedRelationships
-
identifier
Query the cache for the changes to relationships of a resource.
Returns a map of relationship names to RelationshipDiff objects.
type RelationshipDiff =
| {
kind: 'collection';
remoteState: StableRecordIdentifier[];
additions: Set<StableRecordIdentifier>;
removals: Set<StableRecordIdentifier>;
localState: StableRecordIdentifier[];
reordered: boolean;
}
| {
kind: 'resource';
remoteState: StableRecordIdentifier | null;
localState: StableRecordIdentifier | null;
};
Parameters:
-
identifier
StableRecordIdentifier
Returns:
clientDidCreate
-
identifier
-
options
[LIFECYCLE] Signal to the cache that a new record has been instantiated on the client
It returns properties from options that should be set on the record during the create process. This return value behavior is deprecated.
Parameters:
-
identifier
Object -
options
Object
commitWasRejected
-
identifier
-
errors
[LIFECYCLE] Signals to the cache that a resource was update via a save transaction failed.
Parameters:
-
identifier
Object -
errors
Object
didCommit
-
identifier
-
data
[LIFECYCLE] Signals to the cache that a resource was successfully updated as part of a save transaction.
Parameters:
-
identifier
Object -
data
Object
diff
()
public
Generate the list of changes applied to all record in the store.
Each individual resource or document that has
been mutated should be described as an individual
Change
entry in the returned array.
A Change
is described by an object containing up to
three properties: (1) the identifier
of the entity that
changed; (2) the op
code of that change being one of
upsert
or remove
, and if the op is upsert
a patch
containing the data to merge into the cache for the given
entity.
This patch
is opaque to the Store but should be understood
by the Cache and may expect to be utilized by an Adapter
when generating data during a save
operation.
It is generally recommended that the patch
contain only
the updated state, ignoring fields that are unchanged
interface Change {
identifier: StableRecordIdentifier | StableDocumentIdentifier;
op: 'upsert' | 'remove';
patch?: unknown;
}
dump
()
PromiseSerialize the entire contents of the Cache into a Stream
which may be fed back into a new instance of the same Cache
via cache.hydrate
.
Returns:
fork
()
public
Create a fork of the cache from the current state.
Applications should typically not call this method themselves, preferring instead to fork at the Store level, which will utilize this method to fork the cache.
Returns:
Promise
getAttr
-
identifier
-
propertyName
Retrieve the data for an attribute from the cache
Parameters:
-
identifier
Object -
propertyName
Object
Returns:
getErrors
-
identifier
Query the cache for any validation errors applicable to the given resource.
Parameters:
-
identifier
Object
Returns:
getRelationship
-
identifier
-
propertyName
Query the cache for the current state of a relationship property
Parameters:
-
identifier
Object -
propertyName
Object
Returns:
resource relationship object
hasChangedAttrs
-
identifier
Query the cache for whether any mutated attributes exist
Parameters:
-
identifier
Object
Returns:
hasChangedRelationships
-
identifier
Query the cache for whether any mutated attributes exist
Parameters:
-
identifier
StableRecordIdentifier
Returns:
hydrate
-
stream
hydrate a Cache from a Stream with content previously serialized from another instance of the same Cache, resolving when hydration is complete.
This method should expect to be called both in the context of restoring the Cache during application rehydration after SSR AND at unknown times during the lifetime of an already booted application when it is desired to bulk-load additional information into the cache. This latter behavior supports optimizing pre/fetching of data for route transitions via data-only SSR modes.
Parameters:
-
stream
ReadableStream
Returns:
isDeleted
-
identifier
Query the cache for whether a given resource is marked as deleted (but not necessarily persisted yet).
Parameters:
-
identifier
Object
Returns:
isDeletionCommitted
-
identifier
Query the cache for whether a given resource has been deleted and that deletion has also been persisted.
Parameters:
-
identifier
Object
Returns:
isEmpty
-
identifier
Query the cache for whether a given resource has any available data
Parameters:
-
identifier
Object
Returns:
isNew
-
identifier
Query the cache for whether a given resource was created locally and not yet persisted.
Parameters:
-
identifier
Object
Returns:
merge
-
cache
Merge a fork back into a parent Cache.
Applications should typically not call this method themselves, preferring instead to merge at the Store level, which will utilize this method to merge the caches.
Parameters:
-
cache
Cache
Returns:
Promise
mutate
-
mutation
Update resource data with a local mutation. Currently supports operations on relationships only.
Parameters:
-
mutation
Object
patch
-
op
Perform an operation on the cache to update the remote state.
Note: currently the only valid operation is a MergeOperation which occurs when a collision of identifiers is detected.
Parameters:
-
op
Objectthe operation to perform
Returns:
peek
-
identifier
Peek resource data from the Cache.
In development, if the return value is JSON the return value will be deep-cloned and deep-frozen to prevent mutation thereby enforcing cache Immutability.
This form of peek is useful for implementations that want to feed raw-data from cache to the UI or which want to interact with a blob of data directly from the presentation cache.
An implementation might want to do this because de-referencing records which read from their own blob is generally safer because the record does not require retaining connections to the Store and Cache to present data on a per-field basis.
This generally takes the place of getAttr
as
an API and may even take the place of getRelationship
depending on implementation specifics, though this
latter usage is less recommended due to the advantages
of the Graph handling necessary entanglements and
notifications for relational data.
Parameters:
-
identifier
StableRecordIdentifier | StableDocumentIdentifier
Returns:
the known resource data
peekRequest
-
UNKNOWN
Peek the Cache for the existing request data associated with a cacheable request
Parameters:
-
UNKNOWN
StableDocumentIdentifier
Returns:
put
-
doc
Cache the response to a request
Unlike store.push
which has UPSERT
semantics, put
has replace
semantics similar to
the http
method PUT
the individually cacheable e resource data it may contain should upsert, but the document data surrounding it should fully replace any existing information
Note that in order to support inserting arbitrary data
to the cache that did not originate from a request put
should expect to sometimes encounter a document with only
a content
member and therefor must not assume the existence
of request
and response
on the document.
Parameters:
-
doc
StructuredDocument
Returns:
rollbackAttrs
-
identifier
Tell the cache to discard any uncommitted mutations to attributes
Parameters:
-
identifier
Object
Returns:
the names of attributes that were restored
rollbackRelationships
-
identifier
Tell the cache to discard any uncommitted mutations to relationships.
This will also discard the change on any appropriate inverses.
This method is a candidate to become a mutation
Parameters:
-
identifier
StableRecordIdentifier
Returns:
the names of relationships that were restored
setAttr
-
identifier
-
propertyName
-
value
Mutate the data for an attribute in the cache
Parameters:
-
identifier
Object -
propertyName
Object -
value
Object
setIsDeleted
-
identifier
-
isDeleted
Update the cache state for the given resource to be marked as locally deleted, or remove such a mark.
Parameters:
-
identifier
Object -
isDeleted
Object
unloadRecord
-
identifier
[LIFECYCLE] Signals to the cache that all data for a resource should be cleared.
Parameters:
-
identifier
Object
upsert
-
identifier
-
data
-
hasRecord
Push resource data from a remote source into the cache for this identifier
Parameters:
-
identifier
Object -
data
Object -
hasRecord
Object
Returns:
if hasRecord
is true then calculated key changes should be returned
willCommit
-
identifier
[LIFECYCLE] Signals to the cache that a resource will be part of a save transaction.
Parameters:
-
identifier
Object